Hydrogen gas subsurface storage (hss)

Abstract

A method of storing hydrogen gas in a subsurface formation may include compressing hydrogen gas by utilizing a compressor. This may create pressurized hydrogen gas that may be introduced into a subsurface formation through a wellhead to store as reserved hydrogen gas. The reserved hydrogen gas may be stored and maintained in the subsurface formations for a period. Another method in accordance with one or more embodiments of the present disclosure relates to recovering previously stored hydrogen gas from a subsurface storage for energy production. The method may include extracting reserved hydrogen gas from a subsurface formation. The extracted hydrogen gas may be purified by using at least a dehydrator, a pressure swing adsorption unit (PSA) and at least a temperature swing adsorption unit (TSA). The purified hydrogen gas may then be pressurized and used as a fuel for combustion in a turbine-generator unit.

What is claimed: 
     
         1 . A method, comprising:
 compressing a hydrogen gas into a pressurized hydrogen gas by utilizing a compressor;   introducing the pressurized hydrogen gas into a subsurface formation through a wellhead to form a reserved hydrogen gas; and   maintaining the reserved hydrogen gas in the subsurface formation for a period.   
     
     
         2 . The method of  claim 1 , further comprising:
 generating electrical power utilizing a renewable energy source;   producing a gas mixture comprising the hydrogen gas and an oxygen gas via an electrochemical decomposition of water utilizing renewably generated electrical power; and   separating the hydrogen gas from the gas mixture for subsurface storage.   
     
     
         3 . The method of  claim 2 , further comprising purifying the hydrogen gas after separating the hydrogen gas from the gas mixture and before introducing purified, pressurized hydrogen gas into the subsurface formation. 
     
     
         4 . The method of  claim 2 , wherein an electrolyzer unit is utilized to perform the electrochemical decomposition of water. 
     
     
         5 . The method of  claim 3 , wherein an electrolyzer unit is used for decomposition of water and is fluidly coupled with upstream of the compressor, and the compressor is fluidly coupled with upstream of the wellhead. 
     
     
         6 . The method of  claim 1 , wherein purity of the pressurized hydrogen gas may range from 50 to 100% depending on an application. 
     
     
         7 . The method of  claim 1 , wherein the wellhead comprises both fluid couplings and signal couplings for equipment positioned below a surface. 
     
     
         8 . The method of  claim 2 , wherein the renewable energy source is solar energy, and a plurality of solar panels are used for generating electricity power. 
     
     
         9 . The method of  claim 2 , wherein the renewable energy source is wind energy, and a plurality of wind turbines are used for generating electricity power. 
     
     
         10 . The method of  claim 2 , wherein the water used for producing hydrogen gas through electrolysis is sourced from rainwater. 
     
     
         11 . The method of  claim 1 , wherein stored hydrogen gas is introduced into an additional subsurface storage formation before transporting into larger volume subsurface formations. 
     
     
         12 . The method of  claim 2 , further comprising separating oxygen gas from the gas mixture and storing the oxygen gas in a conventional method for future use. 
     
     
         13 . A method, comprising:
 extracting a reserved hydrogen gas from a subsurface to form an extracted hydrogen gas;   purifying the extracted hydrogen gas utilizing at least a dehydrator, a pressure swing adsorption unit (PSA) and at least a temperature swing adsorption unit (TSA) to produce a purified hydrogen gas;   pressurizing the purified hydrogen gas to produce a pressurized hydrogen gas; and   producing energy by combusting the pressurized hydrogen gas in a turbine-generator unit.   
     
     
         14 . The method of  claim 13 , wherein produced energy is utilized as electricity or heat. 
     
     
         15 . The method of  claim 13 , further comprising distributing produced energy in a conventional power grid system for use. 
     
     
         16 . The method of  claim 14 , wherein the reserved hydrogen gas further comprises impurities. 
     
     
         17 . The method of  claim 14 , wherein the extracted hydrogen gas is passed through a separation unit to remove impurities. 
     
     
         18 . The method of  claim 13 , wherein the extracted hydrogen gas is passed through a dehydrator such that purity of dehydrated hydrogen gas is at least 50%. 
     
     
         19 . The method of  claim 13 , wherein the dehydrator also produces water.